From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from saturn.retrosnub.co.uk ([178.18.118.26]:33883 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751378AbcEDHtN (ORCPT ); Wed, 4 May 2016 03:49:13 -0400 Subject: Re: Regression in inv_mpu6050: 4.6.0-rc5 To: Crestez Dan Leonard , One Thousand Gnomes , Michael Welling , mranostay@gmail.com References: <20160426232651.099a18d7@lxorguk.ukuu.org.uk> <20160426230755.GA6235@deathstar> <20160427165613.4d464792@lxorguk.ukuu.org.uk> <5728F3CD.3000801@gmail.com> Cc: linux-kernel@vger.kernel.org, daniel.baluta@intel.com, linux-iio@vger.kernel.org, Greg KH From: Jonathan Cameron Message-ID: <0fd48340-63b7-253e-352c-4f98cf6e19b2@kernel.org> Date: Wed, 4 May 2016 08:49:06 +0100 MIME-Version: 1.0 In-Reply-To: <5728F3CD.3000801@gmail.com> Content-Type: text/plain; charset=windows-1252 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 03/05/16 19:54, Crestez Dan Leonard wrote: > On 05/01/2016 10:58 PM, Jonathan Cameron wrote: >> On 27/04/16 16:56, One Thousand Gnomes wrote: >>> On Tue, 26 Apr 2016 18:07:55 -0500 >>> Michael Welling wrote: >>> >>>> On Tue, Apr 26, 2016 at 11:26:51PM +0100, One Thousand Gnomes wrote: >>>>> >>>>> This now causes us to crash and burn on the ASUS T100TA Baytrail/T >>>>> platforms >>>>> >>>> >>>> I believe this regression has already been patched. >>>> >>>> Check the latest commits in linux-next. >>>> >>>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/log/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c >>>> >>>> See if the latest patches fix your issue. >>> >>> It does - as this is a regression can we please get those fixes into the >>> next -rc ? >>> >> I'm afraid I'm lost in this one - which patch caused the regression and >> which one fixed it? The only patches I can immediately see in next >> both introduce and then squish a similar bug, but neither of them >> has hit Linus' tree yet. >> >> Or are we dealing with what was fixed in: >> c816d9e7 iio: imu: mpu6050: fix possible NULL dereferences >> I had understood that one as more hypothetical than real... >> >> Unfortunately I'm travelling and I suspect that means this will only get >> in just after the release (so for 4.6.1) once I've confirmed which fixes >> we actually need to backport. >> > Commit > c816d9e7: iio: imu: mpu6050: fix possible NULL dereferences > Fixes: > 33da559f: iio: imu: mpu6050: add mpu6500 register settings > > As far as I can tell this crash will always happen when the device is > probed via ACPI. Hi Greg, A quick heads up. Unfortunately this regression has come up whilst I'm travelling and don't have appropriate signing keys with me to do a pull request. Should be able to do one tomorrow evening as I'll back home. Turns out the 'possible' is quite common and causing a mess. Even better the fix actually has a fix as well... Fastest option is probably a cherry pick of: c816d9e7: iio: imu: mpu6050: fix possible NULL dereferences 718ba46e: iio: imu: mpu6050: Fix name/chip_id when using ACPI I'll send you a pull request of my togreg-in-a-hurry branch tomorrow. Sorry for these being so late in the cycle. Anyhow, run for train time. Thanks Jonathan